The present invention relates to toner cartridges and the remanufacture thereof. More particularly, it relates to a retaining clip for a toner cartridge wiper blade assembly, a replacement fastener for a corona grid assembly, and a method for removing and replacing a toner cartridge wiper blade assembly and a corona grid assembly.
Toner "process " cartridges are well known. Such cartridges, commonly referred to simply as toner cartridges, are used in laser beam printers, facsimile machines, electrophotographic copying machines, and other such apparatus to form an image on a piece of paper or other suitable image recording media. In such image forming apparatus, a latent image is formed by selectively exposing a rotating photosensitive drum which has been uniformly charged. Toner is then transferred to the photosensitive drum to form a toner image on the drum. A recording sheet, most commonly paper, is then contacted with the drum so that the toner image is transferred to the sheet for viewing. Finally, a wiper blade contacts the drum and removes any excess toner so that another latent image may be formed on the drum. The wiper blade sweeps the residual toner into a waste toner hopper.
It is also well known to recharge or remanufacture toner cartridges upon the depletion of the original supply of toner. The cartridge housing and many other components are long-lasting and need not be discarded simply due to the depletion of toner. Other components, however, are worn as the toner is depleted and must be replaced when the toner hopper is refilled. Depending upon the type of toner cartridge involved, various methods are used to access the toner hopper and cartridge components for recharging purposes.
It is often necessary to replace the cartridge wiper blade assembly during a recharging operation. Unfortunately, with certain cartridges, removal of the original equipment wiper blade assembly, and the subsequent insertion of a new blade assembly, is very troublesome. For example, in certain cartridges, the wiper blade assembly is positioned in a rear or waste toner hopper region of the cartridge housing. Heretofore, removal of the wiper blade in these cartridges has necessitated removal and subsequent reattachment of the top of the toner waste hopper which has proved to be a difficult and time consuming process. Attempts to replace the wiper blade assembly in these cartridges without removing the waste toner hopper top oftentimes results in damage to the toner cartridge housing. Furthermore, given that toner cartridges are typically recharged numerous times, it is generally desirable to use a method of wiper blade replacement that is quick and easy, yet sufficiently secure to prevent any unwanted movement of the wiper blade assembly.
The wiper blade replacement can be further complicated by the presence of a corona wire grid which blocks convenient access to the wiper blade assembly. If removed, the corona grid must be reattached to the cartridge housing using very small fasteners which are extremely difficult to manipulate and handle.
Accordingly, it has been considered desirable to develop a method for replacing a wiper blade assembly in the above-described types of toner cartridges, along with a device for releasably retaining the replacement wiper blade assembly for ease of subsequent replacement operations. Furthermore, it has been deemed desirable to develop a method and apparatus for securing a corona grid in these cartridges after the same has been removed to facilitate wiper blade removal and replacement.
The subject invention is deemed to meet the foregoing needs and others, and to provide apparatus and methods suitable for use with these particular cartridges.